overheating issues

[pjm8047]

Use an electric fan in front of the radiator.Helps out alot.My new radiator has no shroud runs cool on the highway but slowly starts to warm up at idle .I have my fan on a toggle switch so I turn it on anytime I want

 

[nm9stheham]

Your engine tightness is not the issue. The rings are well past broken in, and the bearings don't heat ot any real degree. (If they do, they seize!) Compression is the only other factor and that should not drop for a looong time. So don't do anything inside the engine; this is purely a cooling system problem.

Things not mentioned so far that can be critical for good cooling at low speeds and idle:
1) Sealing the radiator to the core support; there needs to be good seals on the side and top to make sure that the fan can draw all the air THROUGH the radiator's core not through the gaps on the sides or bottom or top
2) For proper low speed and high speed operation, there is often a seal between the top of the radiator core and the hood; this needs to be in place to make sure the air coming in from the front of the car is forced through the rad core and does not just push over the top of the core support. At idle, this top seal stops hot air from the top of the engine compartment from recirculating over the top of the core support and back through the rad core.
3) You can check the overall heat in the engine bay as as issue by putting some spacers between the hood and the hinges so there is a gap in the back. But, I doubt this is the issue for idle and low speed heating; this problem shows up more often after long, hard runs.
4) The fan shroud needs to have some depth, and not be a flat plate up against the rad core. Here is an example of a totally wrong concept of a 'shroud' in the history of mankind; DON'T DO THIS! Look at the pix in post #23: http://www.forabodiesonly.com/mopar/showthread.php?t=282070
5) This seems silly, but make sure the fan is blowing in the right direction!

And this statment from coloradodave is correct: "Ski: Manufacturers of copper / stock radiators don't want us to buy them? Again, the fact that the car cools going down the road indicates that the radiator (aluminum in this case) is doing its job. " This problem is a problem of airflow through the rad core at low speed and idle. The engine heat output is a lot lower in this situaiton than at cruise, and so if the rad core is getting rid of the heat at cruise, then it can get rid of the lower heat output at low speed/idle with the proper amount of air.

One other thing is the water pump impeller; if it is not setting at the right depth in the pump cavity, it may not pump the full amount of coolant. But I would expect issues at cruise too from this; keep this in the back of your mind. Is this the right pump for this engine?

 

[gtxno1]

Your engine tightness is not the issue. The rings are well past broken in, and the bearings don't heat ot any real degree. (If they do, they seize!) Compression is the only other factor and that should not drop for a looong time. So don't do anything inside the engine; this is purely a cooling system problem.

Things not mentioned so far that can be critical for good cooling at low speeds and idle:
1) Sealing the radiator to the core support; there needs to be good seals on the side and top to make sure that the fan can draw all the air THROUGH the radiator's core not through the gaps on the sides or bottom or top
2) For proper low speed and high speed operation, there is often a seal between the top of the radiator core and the hood; this needs to be in place to make sure the air coming in from the front of the car is forced through the rad core and does not just push over the top of the core support. At idle, this top seal stops hot air from the top of the engine compartment from recirculating over the top of the core support and back through the rad core.
3) You can check the overall heat in the engine bay as as issue by putting some spacers between the hood and the hinges so there is a gap in the back. But, I doubt this is the issue for idle and low speed heating; this problem shows up more often after long, hard runs.
4) The fan shroud needs to have some depth, and not be a flat plate up against the rad core. Here is an example of a totally wrong concept of a 'shroud' in the history of mankind; DON'T DO THIS! Look at the pix in post #23: http://www.forabodiesonly.com/mopar/showthread.php?t=282070
5) This seems silly, but make sure the fan is blowing in the right direction!

And this statment from coloradodave is correct: "Ski: Manufacturers of copper / stock radiators don't want us to buy them? Again, the fact that the car cools going down the road indicates that the radiator (aluminum in this case) is doing its job. " This problem is a problem of airflow through the rad core at low speed and idle. The engine heat output is a lot lower in this situaiton than at cruise, and so if the rad core is getting rid of the heat at cruise, then it can get rid of the lower heat output at low speed/idle with the proper amount of air.

One other thing is the water pump impeller; if it is not setting at the right depth in the pump cavity, it may not pump the full amount of coolant. But I would expect issues at cruise too from this; keep this in the back of your mind. Is this the right pump for this engine?

check the direction of the electric fans if your using if you are using the electric also if your using the traditional fan did you change the pulleys if so they are not spinning fast enough

 

[moperformance]

One thing that I haven't seen mentioned is.....On my Bee the exact same thing occurred until I made a plate out of aluminum under the front bumper. It runs from the bottom of the core support to the inside edge of the front bumper, all the way across the bottom. What was happening was that the hot air under the radiator kept circulating through the lower part in traffic.
Hope this helps!

 

[nm9stheham]

^^^ Well, there is a new one on me...good point! Similar issue as with the seal over the core support to the hood. I just feel certian that if the ariflow to the OP's rad core is right, he will have no more issues, since it cools at speed. (Assuming the water pump works right....)

 

[bigmanjbmopar]

My set up is similar, except I have an 18" flex fan, half shroud made by specter. 14" electric pusher fan in front on a relay set to 200° 180° stat and it seems to work good. Does get up to 200 occasionally in hot weather in stop and go traffic. remember keep the radiator clear as possible to allow the air flow.

Make sure pump is working and stat is working. try redlines water wetter to help out 20° cooler they say?